- Stage 4: 3h 36' 39" (actual), 3h 49' 16" (prediction), 12' 37" slow (5.82% error)
A decade ago, I would have thought our error was fine. Now, I think it's too large! I was unable to watch any of the stage. I did, however, see reports of 20 kph (12.4 mph) tailwinds in a few places and crosswinds in other places. There appeared to be a tailwind component for much of the race. Those who watched the race will surely let me know how much wind played a role in today's action. Kittel's average speed is given below.
- Stage 4: 12.578 m/s (45.28 kph or 28.14 mph)
That's a great speed, but not so large as to raise eyebrows. To give you a feeling for just how sensitive times are to environmental conditions like wind, if we add a 4 kph (2.5 mph) horizontal tailwind to the entirety of Stage 4, we are slow by only 4". That's all it takes! We need to research the stage a little more to see if wind played a role or if Kittel was just flat-out amazing. We know the latter is true!
Tomorrow's 155.5-km (96.6-mi) flat stage begins just across the border into Belgium in Ypres. After a bit to the northeast, the stage mostly takes riders south, finishing in Arenberg Porte du Hainaut. What makes Stage 5 so fun is that is has nine sections of cobblestones in the latter half of the stage. Cobblestone roads make up a total of 15.4 km (9.57 mi) of the final 68.5 km (42.6 mi) of the ride into Arenberg Porte du Hainaut; that's more than 22% of that last 68.5 km. We will be anxious to see how the cobblestones affect racing. Below is our prediction.
- Stage 5: 3h 34' 03" (prediction)
Despite winning three of the first four stages, Kittel sits in 147th place at 19' 50" behind Vincenzo Nibali's, whose great ride in Stage 2 keeps the yellow jersey on his back.